The massive floods that inundated Henan Province in China, and parts of Germany and Belgium, in 2021, offer lessons for the world as a whole: more proactive approach that is opportunity-driven is needed, IHE Delft Professor Chris Zevenbergen told participants in the 5th International Forum on Urban Flood Control and Drainage Capacity, held online on 9 and 10 December in Shanghai.
The two-day international forum 5th International Forum on Urban Flood Control and Drainage Capacity 2021 (IFUFC2021) on urban flood control and drainage capacity focuses on developments related to urban floods in China and the rest of the world.
Chris Zevenbergen, Professor of Flood Resilience of Urban Systems at IHE Delft, speaking on behalf of the China Europe Water platform Partnership Instrument project China-Europe Cooperation on Sponge Cities (CEWP PI CECoSC), highlighted similarities between the 2021 floods in China and Europe.
“Both Chinese and European cities face increased risk of floods and droughts, as well as a shortage of clean water. In China and the EU, the traditional responses to those challenges, particularly related to stormwater, are predominantly reactive and problem-driven rather than pro-active and opportunity-driven, for example with regard to maintenance of infrastructure and urban renewal,” he said.
“A reactive, problem-driven approach focuses only on minimizing risks, while a pro-active approach aims to also maximize the benefits associated with these risk mitigation measures such as increasing the liveability of cities. However, a new approach is emerging in China and in many European cities who are transitioning towards nature-based solutions to create a sustainable and water-sensitive urban future.”
Professor Zevenbergen argued that cities need to transform themselves into so-called sponge cities – that is, they need to incorporate measures that enable urban areas to not only absorb large amounts of water, but also are able to tolerate and to recover more easily from them so that heavy rains do not cause huge damage. Such measures include managing stormwater under extreme conditions with extreme rains which at the same time provide benefits in day-to-day situations with normal rains.